論文集 ＩＳＭＥ ＴＯＫＹＯ ２０００ Ｖｏｌｕｍｅ?

Service Experience of the World's First Large-Bore Gas-lnjection Engine

Tetsugo FUKUDA* Masaki OHTSU** Peter Sunn PEDERSEN***

ABSTRACT

Detailed service experience gained with Mitsui-MAN-B&W 12K80MC-GI-S during the first 14,000 operating hours in a 40MW power plant are described together with experiences of auxiliary equipment like gas compressor and DeNOx system.

After that the paper briefly discusses a comparative study of propulsion alternatives for LNG carriers based on the above service experience.

Finally, new possibilities for the gas-injection engine like exhaust gas re-circulation, turbo-compound system, meehatronic gas-injection and the intelligent engine concept are briefly mentioned.

A high-pressure gas injection system has been jointly developed by Mitsui and MAN B&W Diesel for use in two-stroke as well as four-stroke engines since the early 80'ties. Despite significant advantages, there are still not so many actual plants using gas injection technology, especially for 2-stroke diesel engines - and there are no prime movers for LNG carriers of this type so far.

However, from the environmental point of view, there is increasing interest in utilising clean natural gas in diesel engines, especially for stationary applications such as co-generation plants. For economical as well as environmental reasons, also for propulsion of shuttle tankers and LNG carriers, where the engine uses the Volatile Organic Compounds and boil-off gas as the main fuel, respectively, there is increasing interest in the GI-technology.

In order to break through the situation the world's first large-bore gas injection engine, a 40MW 12K80MC-GI, was built by Mitsui and installed at Mitsui's Chiba works in Ichihara City, Japan. This Chiba GIDE plant serves as a verification plant for the GI-technology and produces electricity at commercial base according to the demand of Tokyo Electric Power Company (TEPCO).

The engine started running in early 1994 and was commissioned on 1st July 1994. Since then some 14,000 operating hours have been accumulated at the end of March 2000 and a very high degree of safety and reliability has been demonstrated. The accumulated service experience of the plant is described in the following.

2. Over all view of Chiba GIDE and operation results

Main particulars of the Chiba GIDE power plant are listed on Table 1 and the system flow diagram is shown in Fig.1.